Crystalline Forms of a Pharmaceutical Compound

ABSTRACT

Described are crystalline forms of the pharmaceutical compound “[9S-(9α,10β,12α)]-5,16-Bis[(ethylthio)methyl]-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3 -fg:3′,2′,1′-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid methyl ester”, as well as methods for their use and preparation.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuing application of U.S. application Ser. No. 10/597,977filed Sep. 12, 2006, which is a U.S. national phase application under 35U.S.C. §371 of International Patent Application No. PCT/DK2005/000127filed Feb. 24, 2005, which claims priority of Danish Patent ApplicationNo. PA200400326, filed on Feb. 27, 2004, and U.S. Provisional PatentApplication No. 60/548,351, filed on Feb. 27, 2004, all of which arehereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to crystalline forms of a compound and theuse of such forms in the preparation of a medicament, in particular forthe treatment of Parkinson's disease.

BACKGROUND OF THE INVENTION

The compound with the structure outlined below is presently in clinicaltrials for Parkinson's disease (Idrugs, 2003, 6(4), 377-383).

This compound is in the following referred to as Compound I. Thechemical name of Compound I is[9S-(9α,10β,12α)]-5,16-Bis[(ethylthio)methyl]-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3′,2′,1′-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylicacid methyl ester.

The following references relate to Compound I, in particular to methodsfor its preparation [J. Med. Chem. 1997, 40(12), 1863-1869; Curr. Med.Chem.—Central Nervous System Agents, 2002, 2(2), 143-155] and itspotential medical uses, mainly in diseases in the central nervous system(CNS), in particular for treatment of neurodegenerative diseases, e.g.Parkinson's disease, Alzheimer's disease, Huntington's disease,peripheral neuropathy, AIDS dementia, and ear injuries such asnoise-induced hearing loss [Progress in Medicinal Chemistry (2002), 40,23-62; Bioorg. Med. Chem. Lett. 2002,12(2), 147-150; Neuroscience,Oxford, 1998, 86(2), 461-472; J. Neurochemistry (2001), 77(3), 849-863;J. Neuroscience (2000), 20(1), 43-50; J. Neurochemistry (2002), 82(6),1424-1434; Hearing Research, 2002, 166(1-2), 33-43].

The following patent documents relate to Compound I, including itsmedical use and synthesis: WO 9402488, WO9749406, U.S. Pat. No.5,621,100, EP 0651754 and EP 112 932.

By the known methods, Compound I is synthesized in a solid amorphousform. The inventors have now discovered 5 crystalline forms of CompoundI (named alpha, beta, gamma, delta and epsilon) thereby providing anopportunity to improve the manufacturing process of Compound I and itspharmaceutical use. There exists a need for crystalline forms, which mayexhibit desirable and beneficial chemical and physical properties. Therealso exists a need for reliable and reproducible methods for themanufacture, purification, and formulation of Compound I to permit itsfeasible commercialisation.

SUMMARY OF THE INVENTION

In a first aspect the present invention relates to crystalline CompoundI, in particular to crystalline forms of Compound I.

Accordingly, the invention provides a crystalline form of Compound Inamed alpha and characterized by one or more of: (i) the X-Ray powderdiffractogram shown in FIG. 1 as measured using CuKα radiation; (ii) anX-Ray powder diffractogram as measured using CuKα radiation havingreflections at 2θ angles: 5.2, 7.3, 8.1, 10.1, 10.4, 11.2, 13.2, 15.1,15.5, 17.3, 21.7, 23.8, 25.1 (iii) the solid state Carbon-13 NMRspectrum shown in FIG. 7; (iv) the NIR reflectance spectrum shown inFIG. 10.

In a further aspect the invention provides a crystalline form ofCompound I named beta and characterized by one or more of: (i) the X-Raypowder diffractogram shown in FIG. 2 as measured using CuKα radiation;(ii) an X-Ray powder diffractogram as measured using CuKα radiationhaving reflections at 2θ angles: 6.6, 8.9, 10.7, 11.4, 11.7, 13.7, 17.0,18.5, 18.8, 19.2, 20.3, 24.4, 30.6; (iii) the solid state Carbon-13 NMRspectrum shown in FIG. 8; (iv) the NIR reflectance spectrum shown inFIG. 11.

In a still further aspect the invention provides a crystalline form ofCompound I named gamma and characterized by one or more of: (i) theX-Ray powder diffractogram shown in FIG. 3 as measured using CuKαradiation; (ii) an X-Ray powder diffractogram as measured using CuKαradiation having reflections at 2θ angles: 7.5, 8.3, 9.6, 11.5, 11.8,12.5, 15.9, 16.3, 16.7, 17.2, 18.0, 19.3, 21.0, 28.1; (iii) the solidstate Carbon-13 NMR spectrum shown in FIG. 9; (iv) the NIR reflectancespectrum shown in FIG. 12.

In a further aspect the invention provides a crystalline form ofCompound I named delta and characterized by one or more of: (i) theX-Ray powder diffractogram shown in FIG. 13 as measured using CuKαradiation; (ii) an X-Ray powder diffractogram as measured using CuKαradiation having reflections at 2θ angles: 7.3, 8.3, 9.7, 11.1, 11.7,12.1, 15.6, 16.1, 17.3, 18.3, 20.9, 22.1, 22.2, 25.7, 25.8.

In a further aspect the invention provides a crystalline form ofCompound I named epsilon and characterized by one or more of: (i) theX-Ray powder diffractogram shown in FIG. 15 as measured using CuKαradiation; (ii) an X-Ray powder diffractogram as measured using CuKαradiation having reflections at 2θ angles: 8.9, 9.2, 10.2, 12.6, 14.2,14.6, 17.0, 18.6, 20.4, 21.1, 23.9, 25.2.

The invention further relates to methods for preparing the crystallineforms of the invention and the use of such forms in the preparation of amedicament comprising Compound I as an active ingredient.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: Shows an x-ray powder diffractogram of Compound I alpha form.

FIG. 2: Shows an x-ray powder diffractogram of Compound I beta form.

FIG. 3: Shows an x-ray powder diffractogram of Compound I gamma form.

FIG. 4: Shows a DSC thermogram of Compound I alpha form.

FIG. 5: Shows a DSC thermogram of Compound I beta form.

FIG. 6: Shows a DSC thermogram of Compound I gamma form.

FIG. 7: Shows a solid state Carbon-13 NMR spectrum of Compound I alphaform.

FIG. 8: Shows a solid state Carbon-13 NMR spectrum of Compound I betaform.

FIG. 9: Shows a solid state Carbon-13 NMR spectrum of Compound I gammaform.

FIG. 10: Shows a NIR reflectance spectrum of Compound I alpha form.

FIG. 11: Shows a NIR reflectance spectrum of Compound I beta form.

FIG. 12: Shows a NIR reflectance spectrum of Compound I gamma form.

FIG. 13: Shows an x-ray powder diffractogram of Compound I delta form.

FIG. 14: Shows a DSC thermogram of Compound I delta form.

FIG. 15: Shows an x-ray powder diffractogram of Compound I epsilon form.

FIG. 16: Shows a DSC thermogram of Compound I epsilon form.

FIG. 17: Shows the conformation of one of the molecules (molecule 1) inCompound I alpha form.

FIG. 18: Shows the conformation of the other molecule (molecule 2) inCompound I alpha form.

FIG. 19: Shows the packing of the molecules in Compound I alpha form.

Further details for the figures are revealed in the Examples below.

DETAILED DESCRIPTION OF THE INVENTION

The discovery of a crystalline form of a pharmaceutically usefulcompound provides an opportunity to improve the performancecharacteristics of the pharmaceutical product and the manufacturingprocess.

Differences in physical properties, such as stability (shelf-life),bioavailability, solubility, and dissolution rate, exhibited by thedifferent solid forms of a compound are important factors in themanufacturing and formulation of a compound. Differences in stabilitycan result from changes in chemical reactivity (e.g. oxidation) ormechanical changes (e.g. tablets crumble on storage can lead to theconversion to a thermodynamically more stable crystal form) or both. Thephysical properties of a solid form are important in processing, e.g.one solid form might be more difficult to filter and wash free ofimpurities. This can be due to differences in particle shape and sizedistribution between one crystalline form relative to the other and theamorphous form.

Additionally, for drugs that exist in different crystalline forms andwhich are sold in solid form it is generally important for both medicaland commercial reasons to produce and market a known crystalline form.The discovery of crystalline Compound I and the existence of 5crystalline forms enable the development of a defined crystalline formin place of an amorphous solid. Also, the physical properties of thecrystalline Compound I offer advantages for formulation development andtablet preparation, e.g. direct compression is facilitated by having adefined crystal form.

Crystalline compounds are generally more stable than the correspondingamorphous compound, and this is particularly important in the case ofthe air sensitive and light sensitive Compound I.

Experiments were carried out in a Heraeus Suntest CPS+ for thecrystalline forms alpha, beta and gamma where the solid compound wasexposed to light for 14 h at 650 W. The light treatment led to almost60% degradation of the amorphous substance while the crystalline formsshowed less than 30% degradation.

Compound I contains two sulphur atoms and is easily oxidised to acomplex mixture of sulphones and sulphoxides. This sensitivity tooxidation requires great care during purification of Compound I. Thepresent invention, which makes purification of Compound I bycrystallisation possible, reduces the levels of oxidised compounds ascompared to the product obtained when the inventors have used othermethods of purification such as chromatography. In addition Compound Icontains an active ester group which may undergo transesterificationreactions and it is also susceptible to hydrolysis.

In the final step in the synthesis of Compound I, the desired thiolethyl side chains are introduced using ethyl mercaptan as a reactant [J.Med. Chem. 1997, 40(12), 1863-1869; Curr. Med. Chem.—Central NervousSystem Agents, 2002, 2(2), 143-155]. Ethyl mercaptan has acharacteristic strong odour, which is undesirable in a pharmaceuticalproduct. The isolation of Compound I as an amorphous solid results ininclusion of ethyl mercaptan in the solid product, while the levels ofthis undesired reactant is reduced through crystallisation.

Additionally, the physical characteristics of the crystalline forms ofthe invention improve the isolation step for example by decreasing thefiltration times compared to the amorphous form of Compound I, which isof great significance for the large scale manufacturing of Compound I.In this respect the delta form was found to have better filtrationproperties than the alpha form.

A further difference in the physical chemical properties of thecrystalline forms compared to the amorphous form is the higher meltingpoints, cf. Table I below in Example 9, which can give advantages infurther processing.

As indicated above the inventors have now discovered that Compound I canbe made in a crystalline form and that there is at least 5 crystallineforms Compound I, herein named alpha, beta, gamma, delta and epsilon.

Thus, in a broad aspect the invention relates to crystalline Compound I,in particular to a crystalline form of Compound I. As used herein theexpression “a crystalline form of Compound I” comprises any crystallineforms of Compound I, i.e. in contrast to the amorphous form. Inparticular the term “crystalline Compound I” includes the alpha, beta,gamma, delta and/or epsilon crystalline form of Compound I, which formsare as defined herein.

Crystalline forms of a compound are differentiated by the positions ofthe atomic nuclei in the unit cell of the solidified compound. Thedifferences produce different macroscopic properties like thermalbehaviour, vapour permeability and solubility, which as indicated abovehave practical consequences in pharmacy. The various forms describedherein may be distinguishable from one another through the use ofvarious analytical techniques known to one of ordinary skill in the art.Such techniques include, but are not limited to X-ray powder diffraction(XRD), differential scanning calorimetry (DSC), solid-state nuclearmagnetic resonance (NMR) spectroscopy, and Near-infrared (NIR)spectroscopy. Crystalline forms of a compound are most readilydistinguished by X-ray analysis. Single crystal X-ray crystallographyyields data that can be used to determine the positions of the nuclei,which in turn may be visualized with computer or mechanical models, thusproviding a three-dimensional image of the compound. While singlecrystal X-ray studies provide unmatched structural information, they areexpensive and quality data can sometimes be difficult to acquire. PowderX-ray diffraction is used more frequently by the pharmaceutical industryto characterize new crystalline forms of drugs than is single crystalX-ray analysis. Powder X-ray diffraction yields a fingerprint that isunique to the crystalline form and is able to distinguish it from theamorphous compound and all other crystalline forms of the compound.

Accordingly, one embodiment of the invention relates to a crystallineform of Compound I named alpha characterized by the X-Ray powderdiffractogram shown in FIG. 1 as measured using CuKα radiation. In afurther embodiment the alpha form of Compound I is characterized byreflections in the X-Ray powder diffractogram as measured using CuKαradiation at 2-theta angles: 5.2, 10.1, 10.4, 13.2, 15.1, 25.1. Thealpha form of Compound I may also be characterized by having reflectionsin the X-Ray diffractogram as measured using CuKα radiation at 2θangles: 5.2, 7.3, 8.1, 10.1, 10.4, 11.2, 13.2, 15.1, 15.5, 17.3, 21.7,23.8, 25.1. The alpha form of Compound I may also be characterized bythe solid state Carbon-13 NMR spectrum shown in FIG. 7. The alpha formof Compound I may also be characterized by the NIR reflectance spectrumshown in FIG. 10. The alpha form of Compound I may also be characterizedby having a melting point in the range of 180-190° C. The alpha form ofCompound I may also be characterized by having DSC thermogramsubstantially in accordance with that shown in FIG. 4. The alpha form ofCompound I may also be characterized by a DSC thermogram having anendotherm from about 170° C. to about 200° C. The crystal structure ofthe alpha form (Example 8.5) has a space in the crystal lattice that mayor may not be occupied by a smaller solvent, in particular a water or amethanol molecule. Thus, the crystalline alpha form of Compound I can bea solvate of varying amounts of water and/or methanol.

Accordingly, the invention also relates to a crystal form characterizedby having a crystal structure with the following characteristics at 122K: Space group: P2₁2₁2₁, Unit cell dimensions: a=10.227(2) Å,b=23.942(2) Å and c=24.240(2) Å, α=90°, β=90°, γ=90°, 2 molecules in theasymmetric unit. As the asymmetric unit in this crystal structurecontains 2 molecules of Compound I and one solvent site, full occupancyof the solvent site leads to a hemi-solvate. The invention furtherrelates to the above indicated crystal structure having atom positionssubstantially as described by the coordinates in Tables 2-4.

When indicating herein for the X-Ray powder diffractogram data thereflections (peaks) it is understood that the reflections are expressedin degrees (at 2θ angles, i.e. at 2-theta angles).

A further embodiment relates to a crystalline form of Compound I namedbeta characterized by the X-Ray powder diffractogram shown in FIG. 2 asmeasured using CuKα radiation.

In a further embodiment, the beta form is characterized by reflectionsin the X-Ray powder diffractogram as measured using CuKα radiation at2-theta angles: 6.6, 8.9, 10.7, 11.7, 24.4, 30.6. The beta form ofCompound I may also be characterized by having reflections in the X-Raydiffractogram as measured using CuKα radiation at 2θ angles: 6.6, 8.9,10.7, 11.4, 11.7, 13.7, 17.0, 18.5, 18.8, 19.2, 20.3, 24.4, 30.6. Thebeta form of Compound I may also be characterized by the solid stateCarbon-13 NMR spectrum shown in FIG. 8. The beta form of Compound I mayalso be characterized by the NIR reflectance spectrum shown in FIG. 11.The beta form of Compound I may also be characterized by having amelting point in the range of 209-213° C., preferably about 211° C. Thebeta form of Compound I may also be characterized by having DSCthermogram substantially in accordance with that shown in FIG. 5. Thebeta form of Compound I may also be characterized by a DSC thermogramhaving an endotherm from about 205° C. to about 220° C.

A further embodiment relates to a crystalline form of Compound I namedgamma characterized by the X-Ray powder diffractogram shown in FIG. 3 asmeasured using CuKα radiation. In one embodiment, the gamma form ischaracterized by reflections in the X-Ray powder diffractogram asmeasured using CuKα radiation at 2-theta angles: 9.6, 11.5, 12.5, 16.7,19.3, 28.1. The gamma form of Compound I may also be characterized byhaving reflections in the X-Ray diffractogram as measured using CuKαradiation at 2θ angles: 7.5, 8.3, 9.6, 11.5, 11.8, 12.5, 15.9, 16.3,16.7, 17.2, 18.0, 19.3, 21.0, 28.1. The gamma form of Compound I mayalso be characterized by the solid state Carbon-13 NMR spectrum shown inFIG. 9. The gamma form of Compound I may also be characterized by theNIR reflectance spectrum shown in FIG. 12. The gamma form of Compound Imay also be characterized by having a melting point in the range of212-218° C. The gamma form of Compound I may also be characterized byhaving DSC thermogram substantially in accordance with that shown inFIG. 6. The gamma form of Compound I may also be characterized by a DSCthermogram having an endotherm from about 210° C. to about 225° C.

A further embodiment relates to a crystalline form of Compound I nameddelta characterized by the X-Ray powder diffractogram shown in FIG. 13as measured using CuKα radiation. In one embodiment, the delta form ischaracterized by reflections in the X-Ray powder diffractogram asmeasured using CuKα radiation at 2-theta angles: 9.7, 12.1, 16.1, 18.3,22.1, 22.2, 25.7, 25.8. The delta form of Compound I may also becharacterized by having reflections in the X-Ray diffractogram asmeasured using CuKα radiation at 2θ angles: 7.3, 8.3, 9.7, 11.1, 11.7,12.1, 15.6, 16.1, 17.3, 18.3, 20.9, 22.1, 22.2, 25.7, 25.8. The deltaform of Compound I may also be characterized by having a melting pointin the range of 211-223° C. The delta form of Compound I may also becharacterized by having DSC thermogram substantially in accordance withthat shown in FIG. 14. The delta form of Compound I may also becharacterized by a DSC thermogram having an endotherm from about 210° C.to about 228° C.

A further embodiment relates to a crystalline form of Compound I namedepsilon characterized by the X-Ray powder diffractogram shown in FIG. 15as measured using CuKα radiation. In one embodiment, the epsilon form ofCompound I is characterized by reflections in the X-Ray powderdiffractogram as measured using CuKα radiation at 2-theta angles: 8.9,9.2, 10.2, 14.6. The epsilon form of Compound I may also becharacterized by having reflections in the X-Ray diffractogram asmeasured using CuKα radiation at 2θ angles: 8.9, 9.2, 10.2, 12.6, 14.2,14.6, 17.0, 18.6, 20.4, 21.1, 23.9, 25.2. The epsilon form of Compound Imay also be characterized by having a melting point in the range of180-185° C. The epsilon form of Compound I may also be characterized byhaving DSC thermogram substantially in accordance with that shown inFIG. 16. The epsilon form of Compound I may also be characterized by aDSC thermogram having an endotherm from about 175° C. to about 190° C.

The invention further relates to any mixtures of the crystalline formsof the invention, e.g. a mixture of the alpha and gamma crystalline formof Compound I.

As used herein expressions like “crystalline form of Compound Icharacterized by the X-Ray powder diffractogram shown in FIG. 1) asmeasured using CuKα” mean the crystalline form of Compound I having anX-ray powder diffractogram substantially similar to FIG. 1, i.e.exhibiting an X-ray powder diffraction pattern as exemplified in thatFigure and measured under comparable conditions as described in Example7.1 or by any comparable method using CuKα radiation. This definitionalso applies mutatis mutandis to the NMR and NIR Figures, and all otherX-Ray data described herein (e.g. X-Ray peak data) and for all of thefive crystal forms identified, i.e. alpha, beta, gamma, delta andepsilon, respectively, such that margins of analytical variations aretaken into consideration.

The solid state Carbon-13 NMR spectra referred to herein is preferablymeasured using a sample spinning speed of 5000 Hz on a spectrometer witha CP-MAS probe. Thus, the NMR spectrum is preferably provided asdescribed in Example 7.2 or by any comparable method. The NIRreflectance spectra referred to herein is preferably provided asdescribed in Example 7.3 or by any comparable method, in particular witha resolution 2 cm⁻¹ and correction of baseline shift and slope withMultiplicative Scatter Correction (MSC).

In further embodiments, the invention relates to a crystalline form ofCompound I, which is substantially pure. The term “substantially pure”,as used herein, means that the crystalline form of Compound I, e.g. thealpha, beta, gamma, delta or epsilon form, is having a purity of atleast about 90% including, e.g., at least about 93%, and at least about95%.

The amorphous form of Compound I melts at a temperature about 150° C.which is easy to distinguish from the melting points of the hereindescribed crystalline forms of Compound I, cf. Table 1 in Example 9.Accordingly, within the invention is also crystalline Compound I havinga melting point which is at least 175° C., or at least 180° C., such asin the range of 175° C.-225° C., 180° C.-225° C., 180° C.-220° C., or181° C.-218° C., alternatively in the range of 180° C.-190° C. or210-225° C.

The term “melting point” as used herein means the onset value of themelting endotherm as measured by DSC, cf. Example 7.4.

A further embodiment, relates to solid Compound I containing crystallineCompound I alpha form. The invention also relates to solid Compound Iconsisting mainly of the crystalline alpha form of Compound I describedherein. The term “mainly” in the present context means that the solidCompound I consists of at least 75%, such as at least 80%, at least 90%,or at least 95% crystalline alpha form of the total Compound I present.

A further embodiment relates to solid Compound I containing crystallineCompound I beta form. The invention also relates to solid Compound Iconsisting mainly of the crystalline beta form of Compound I describedherein. The term “mainly” in the present context means that the solidCompound I consists of at least 75%, such as at least 80%, at least 90%,or at least 95% crystalline beta form of the total Compound I present.

A further embodiment relates to solid Compound I containing crystallineCompound I gamma form. The invention also relates to solid Compound Iconsisting mainly of the crystalline gamma form of Compound I describedherein. The term “mainly” in the present context means that the solidCompound I consists of at least 75%, such as at least 80%, at least 90%,or at least 95% crystalline gamma form of the total Compound I present.

A further embodiment relates to solid Compound I containing crystallineCompound I delta form. The invention also relates to solid Compound Iconsisting mainly of the crystalline delta form of Compound I describedherein. The term “mainly” in the present context means that the solidCompound I consists of at least 75%, such as at least 80%, at least 90%,or at least 95% crystalline delta form of the total Compound I present.

A further embodiment relates to solid Compound I containing crystallineCompound I epsilon form. The invention also relates to a solid CompoundI consisting mainly of the epsilon form of Compound I described herein.The term “mainly” in the present context means that the solid Compound Iconsists of at least 75%, such as at least 80%, at least 90%, or atleast 95% crystalline epsilon form of the total Compound I present.

Broadly speaking, the novel crystalline forms of Compound I may beprepared by a variety of methods, including but not limited tocrystallizing Compound I from a suitable solvent. Compound I may beprepared using methods known in the art, such as those described herein.By way of general guidance, Compound I may be mixed with a suitablesolvent which may be heated to facilitate the dissolution of Compound I.The combination of solvent and Compound I may also be heated tofacilitate assist the subsequent conversion to the crystalline form.Preferred temperatures in this regard may range from about 30° C. toabout the boiling point (i.e., the reflux temperature) of the solvent.More preferred temperatures may range from about 60° C. to about theboiling point of the solvent. The resulting mixture of solvent andCompound I may be cooled to initiate and/or continue crystallization.The mixture is preferably cooled (i.e. including natural cooling toambient temperature) to a temperature which ranges from, e.g., aboutminus 20° C. to about 20° C., e.g. to ambient temperature. Theprecipitated solids may be isolated from the cooled mixture by forexample filtration or centrifugation, and if necessary washed with asuitable solvent such as, but not limited to, the solvent employed forthe crystallization, and dried in vacuo at ambient or slightly elevatedtemperature, e.g. under a nitrogen purge.

Seed crystals may be added to any crystallization mixture to promotecrystallization.

As indicated above crystalline Compound I, in particular the differentcrystal forms of the invention may be prepared by (a) dissolvingCompound I in a suitable solvent, (b) crystallizing by precipitationCompound I from the solvent, and (c) separating the solvent from theobtained crystalline Compound I; or alternatively by a processcomprising the steps of: (a) suspending Compound I in suitable solventfor a period of time sufficient to convert it into the crystalline form,and (b) separating the alcohol from the obtained crystalline Compound I.Below is described how different solvents can be used to make thedifferent crystal forms of Compound I, alpha, beta, gamma, delta andepsilon. In a preferred embodiment, the method of the invention forpreparing crystalline Compound I, including the alpha, beta, gamma,delta or epsilon form, comprises crystallizing by precipitation CompoundI from a suitable solvent and separating the solvent form the obtainedcrystalline Compound I. It is understood in that when referring hereinto the preparation of the different crystal forms of the invention, anda product obtainable or more specifically a product obtained by suchmethods this also applies to “a solid Compound I containing crystallineCompound I”, in particular as described above “a solid Compound Iconsisting mainly of one particular crystalline form of Compound I”,e.g. the alpha, beta, gamma, delta or epsilon form.

Accordingly, in one aspect the invention relates to a method forpreparing crystalline Compound I, characterised in that said crystallineCompound I is formed in a solvent selected from the group consisting of:(i) methanol with 0% to about 8% water; (ii) an aliphatic C₃-C₆ alcohol(e.g. 1-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol) with4-8% water (e.g. 1-butanol with 4% water; 1-propanol with 4% water,1-pentanol with 4% water, tert-butanol with 7% water, 2-butanol with 4%water); (iii) an ester of acetic acid with at least 4% water present,wherein said ester of acetic acid is defined by the formula CH₃CO₂R,where R is a C₁-C₆-alkyl, e.g. ethyl acetate or isopropyl acetate (e.g.ethyl acetate with 4% water or isopropyl acetate with 6% water). Theinvention also relates to the crystalline Compound I obtainable, inparticular obtained, by such method. In a preferred embodiment, thismethod leads to the formation of crystalline Compound I alpha form.

In a further aspect, the invention relates to a method for preparingcrystalline Compound I, characterised in that said crystalline CompoundI is formed in the solvent isopropyl acetate. The invention also relatesto the crystalline Compound I obtainable, in particular obtained, bysuch method. In a preferred embodiment, this method leads to theformation of crystalline Compound I beta form.

In a further aspect, the invention relates to a method for preparingcrystalline Compound I, characterised in that said crystalline CompoundI is formed in a solvent selected from the group consisting of: (i) analiphatic C₁-C₃ nitrile (e.g. acetonitrile, propionitrile) with up toabout 12% water (e.g. propionitrile with 4% water or acetonitrile with12% water), it is understood that propionitrile (CH₃CH₂CN) is aC₃-nitrile; (ii) ethanol with 0% to about 8% water: (iii) an aliphaticC₃-C₆ alcohols (e.g. 1-propanol or 1-butanol) with at least about 10%water (e.g. 1-propanol 10% water, 1-butanol 10% water); (iv) ethylacetate reagent grade. By the term “ethyl acetate reagent grade” ismeant less than 0.5% water. The invention also relates to thecrystalline Compound I obtainable, in particular obtained, by suchmethod. In a preferred embodiment, this method leads to the formation ofcrystalline Compound I gamma form.

In a further embodiment, the invention relates to a method for preparingcrystalline Compound I, characterised in that said crystalline CompoundI is formed in a solvent selected from the group consisting of: (i) analiphatic C₂-C₆ alcohol (e.g. ethanol, cyclopropylmethanol or 1propanol) with less than 4% water, e.g. less than 3%, e.g. about 2%(e.g. cyclopropyl methanol, 1 propanol 2% water, ethanol 2% water (withno stirring). The invention also relates to the crystalline Compound Iobtainable, in particular obtained, by such method. In a preferredembodiment, this method leads to the formation of crystalline Compound Idelta form.

In a further embodiment, the invention relates to a method for preparingcrystalline Compound I, characterised in that said crystalline CompoundI is formed in the solvent butyl nitrile (CH₃CH₂CH₂CN). The inventionalso relates to the crystalline Compound I obtainable, in particularobtained, by such method. In a preferred embodiment, this method leadsto the formation of crystalline Compound I epsilon form.

It has also been found that each of the crystalline form alpha and betacan be converted to the crystalline gamma form, in the presence of asuitable solvent, in particular acetonitrile as shown in Example 6.1.The crystalline beta form can be converted to the crystalline alpha formin the presence of methanol as shown in Example 6.1.

The invention also relates to a crystalline product, in particular thecrystalline forms of Compound I obtainable, or in a preferred embodimentobtained, by a process described herein for the preparation ofCrystalline Compound I.

The invention in a further aspect relates to a process for thepreparation of Compound I comprising converting a crystalline form ofCompound I (e.g. the alpha, beta or gamma form as described herein orany mixtures hereof) into the amorphous form of Compound I. Such processin a preferred embodiment comprises the steps of: (a) dissolvingcrystalline Compound I in an aromatic solvent, i.e. an aromatichydrocarbon, preferably an alkyl-benzene such as xylene or toluene, (b)precipitating Compound I from the aromatic solvent; and (c) separatingthe aromatic solvent from the precipitated amorphous Compound I.

As indicated above the formation of crystalline Compound I is veryuseful inter alia as a purification step in the manufacturing ofCompound I for pharmaceutical use.

The invention in one aspect relates to a process for the manufacturingof Compound I comprising a crystallization step as described herein.Thus, one embodiment of the invention relates to a method for themanufacturing of Compound I, which method comprises a step whereinCompound I is converted to crystalline Compound I. It is understood thatthe crystalline Compound I of the invention may be prepared by a methodas described herein, e.g. by precipitating Compound I in crystallineform from a solvent as described herein and separating the obtainedcrystalline Compound I from the solvent.

The invention in particular relates to method for the manufacturing ofCompound I wherein the Compound I is converted to crystalline Compound,including a crystalline form of the invention, e.g. the alpha or gammaform from a crude mixture of Compound I. The term crude mixture in thiscontext means that the mixture comprises impurities, e.g. oxidationproducts derived from Compound I which it is desired to remove. Thecrude mixture may be separated directly from the reaction mixture, orthe crude reaction mixture may have been subjected to some initialpurification, e.g. treating with a base. The invention further relatesto the use of a crystalline Compound I or a solid of the invention inthe preparation of a medicament comprising Compound I as an activeingredient.

Accordingly, the invention also relates to a method for themanufacturing of a pharmaceutical composition of Compound I, whichmethod comprises preparing said composition from crystalline Compound Ias defined herein, e.g. obtained by a method as described herein,including a crystalline form or a solid of the invention. One specificembodiment relates to such use of the alpha or gamma form of theinvention for the preparation of a pharmaceutical composition. Asdescribed earlier, preparing the formulations from a defined crystalform has the advantage of improved purity and yield and by having welldefined properties, such as solubility. In this respect, the inventionalso provides a pharmaceutical composition comprising an effectiveamount of Compound I obtainable or obtained by a method of the inventionfor the preparation of crystalline Compound I, including a crystallineform of the invention, e.g. from the alpha or gamma form. Thepharmaceutical composition may be any composition found suitable foradministration of Compound I, e.g. a solid dispersion formulation or asolid solution formulation.

In one embodiment, the crystalline product of the invention, i.e.including in particular the alpha, beta, gamma, delta or epsiloncrystalline form, or mixtures thereof, may be formulated into a solidsolution or a solid dispersion. A solid solution may be prepared bydissolving the crystalline product of the invention in a molten vehicle.The solid solution is formed upon cooling to ambient temperature. Asolid dispersion may be prepared by dispersing the crystalline productof the invention in a molten vehicle. The solid dispersion is formedupon cooling to ambient temperature. The vehicle used to prepare thesolid solution or solid dispersion may be one component or a mixture ofmore components. The vehicle used to prepare the solid solution or thesolid dispersion is normally solid or semi-solid at room temperature andnormally it has a sticky, oily or waxy character. However, the vehiclemay also be fluid at room temperature or even at temperature below 5° C.As examples of vehicles can be mentioned polyethylene glycols (PEG),poloxamers, esters of polyethylene glycols, waxes, glycerides, fattyacid alcohols, fatty acids, sugar alcohols, vitamin E and derivatives ofvitamin E. The solid solution or solid dispersion may be used as is oralternatively formulated into pharmaceutical compositions like tablets,capsules etc. The solid solution and solid dispersion can also beprepared by other methods as for example by the solvent method or thefusion method (Serajuddin, A. T. M., Journal of Pharmaceutical Sciences,Vol. 88, 1058-1066). One embodiment of the invention relates to apharmaceutical composition which is a solid solution made fromcrystalline Compound I of the invention, e.g. from the crystalline alphaor gamma form of the invention.

Thus, the crystalline product of the invention, in particular the alpha,beta, gamma, delta or epsilon crystalline forms, or mixtures thereof canbe used in the preparation of a pharmaceutical composition with CompoundI in solution, e.g. a composition similar to those disclosed in U.S.Pat. No. 6,200,968.

Within the invention is also a pharmaceutical composition comprising aneffective amount of crystalline Compound I as described herein, inparticular the alpha, beta, gamma, delta or epsilon forms defined hereinor mixtures thereof, and a pharmaceutically acceptable carrier.

The crystalline product of the invention, i.e. including the crystallinealpha, beta, gamma, delta or epsilon form, or mixtures thereof, may beformulated into a variety of pharmaceutical compositions. Examples ofsuch formulations comprising a crystalline product of the invention(e.g. crystalline alpha, beta, gamma, delta or epsilon forms) aretablets, capsules, granules, powders, suppositories and suspensions. Theexpression “crystalline product of the invention” means a crystallineCompound I or a solid Compound I as described herein, i.e. by “solidCompound I” is in the present context understood a solid Compound Iconsisting mainly of crystalline Compound I as compared to amorphousCompound.

The pharmaceutical compositions according to the invention may beformulated with pharmaceutically acceptable carriers or diluents as wellas any other adjuvants and excipients, e.g. in accordance withtechniques such as those disclosed in Remington: The Science andPractice of Pharmacy, 19 Edition, Gennaro, Ed., Mack Publishing Co.,Easton, Pa., 1995.

The pharmaceutical compositions may be specifically formulated foradministration by any suitable route such as the oral, rectal, nasal,pulmonary, topical (including buccal and sublingual), transdermal,intracisternal, intraperitoneal, vaginal and parenteral (includingsubcutaneous, intramuscular, intrathecal, intravenous and intradermal)route, the oral route being preferred. It will be appreciated that thepreferred route will depend on the general condition and age of thesubject to be treated, the nature of the condition to be treated and theactive ingredient chosen.

In an embodiment of the pharmaceutical composition, Compound I isadministered in an amount of from about 0.001 to about 100 mg/kg bodyweight per day. Compound I may, e.g. be administered in a unit dosageform containing said compound in an amount of about 0.01 to 100 mg. Thetotal daily dose is, e.g., in the range of about 0.05-500 mg. Theformulations may conveniently be presented in unit dosage form bymethods known to those skilled in the art. A typical unit dosage formfor oral administration one or more times per day such as 1 to 3 timesper day may contain from 0.01 to about 1000 mg, preferably from about0.05 to about 500 mg. For parenteral routes such as intravenous,intrathecal, intramuscular and similar administration, typically dosesare in the order of about half the dose employed for oraladministration.

As indicated above, the following embodiments are within the invention:Crystalline Compound I for use as a medicament; the crystalline alphaform for use as a medicament; the crystalline beta form for use as amedicament; the crystalline gamma form for use as a medicament, thecrystalline delta form for use as a medicament; the crystalline epsilonform for use as a medicament.

The invention further relates to the use of crystalline Compound I asdescribed herein e.g. the alpha, beta, gamma, delta or epsilon formdefined herein or mixtures thereof, in the preparation of a medicamentfor the treatment of a CNS disease, e.g., for treatment of aneurodegenerative disease, such as, e.g., Parkinson's disease,Alzheimer's disease, Huntington's disease, peripheral neuropathy, AIDSdementia, or ear injuries including noise-induced hearing loss.

Similarly, within the invention is also a method for treating aneurodegenerative disease, such as e.g. Parkinson's disease, Alzheimer'sdisease, Huntington's disease, peripheral neuropathy, AIDS dementia, orear injuries including noise-induced hearing loss, comprisingadministering a pharmaceutically effective amount of crystallineCompound I as described herein, e.g. the alpha, beta, gamma form, deltaor epsilon defined herein or mixtures thereof.

The above medical uses and pharmaceutical compositions, e.g. fortreatment of Parkinson's disease, of crystalline Compound I and acrystalline form of the invention, is likewise applicable to the solidCompound I defined herein as comprising a crystalline form of theinvention, in particular a solid Compound I consisting mainly of acrystalline form of the invention.

The term “treatment” in connection with a disease as used herein alsoincludes prevention as the case may be. The term “disease” as usedherein also includes a disorder as the case may be.

The invention disclosed herein is further illustrated by the followingnon-limiting examples.

EXAMPLES

In the following the starting material “Compound I” may, e.g., beprepared as described by Kaneko M. et al in J. Med. Chem. 1997, 40,1863-1869.

Example 1 Preparation of Crystalline Alpha Form of Compound I

Method I):

6.0 g amorphous Compound I was dissolved in 30 ml acetone. 0.6 gpotassium carbonate was added and the suspension was stirred at roomtemperature for 1 hour before it was filtered to remove potential minorinsoluble impurities and inorganic salts. The filter cake was washedwith acetone. The filtrate was then evaporated on a rotary evaporatorunder reduced pressure at 60° C. to a final volume of 10 ml to which 100ml methanol was added slowly. The product separated as an oil, whichalmost dissolved on heating to reflux. Subsequently the residualinsoluble impurities were removed by filtration. The filtrate was leftwith stirring at room temperature. A crystalline solid separated and wasisolated by filtration. The filter cake was washed with methanol anddried in vacuo at 60° C. overnight. Yield 2.83 g (47%), mp=182.4° C.(DSC onset value), Weight loss by heating: 0.5%, Elemental analysis:6.71% N, 63.93% C, 5.48% H, theoretical values corrected for 0.5% H₂O:6.79% N, 64.05% C, 5.43% H. XRPD analysis conforms with the alpha form.

Method II):

5 g amorphous Compound I was dissolved in 25 ml acetone by gentleheating. 10 ml Methanol was added very slowly until the solution gotturbid. The solution was allowed to cool to room temperature by naturalcooling. The suspension was filtered and the filter-cake discarded.During filtration more material precipitated in the filtrate. Thefiltrate was heated until all material redissolves. Cold methanol wasthen added to the solution until precipitation was observed. Theslightly turbid solution was then heated until all material was insolution. The solution was allowed to cool to room temperature, and theprecipitate was removed by filtration. The second filter-cake wasdiscarded. During the filtration some material separated in thefiltrate. Heating redissolved the beginning crystallisation in thefiltrate. Cold methanol was then added to the solution untilprecipitation was observed. The suspension was heated until a clearsolution was obtained. The solution was allowed to reach roomtemperature by natural cooling. After a short period of time (15 min)precipitation begun. The precipitated pale yellow product was isolatedby filtration and dried in vacuo at 50° C. overnight.

mp=188.9° C. (DSC onset value), Weight loss by heating: 0.3%, Elementalanalysis: 6.53% N, 64.33% C, 5.43% H, theoretical values: 6.82% N,64.37% C, 5.37% H. XRPD analysis conforms with the alpha form.

Method III:

0.5g Compound I in a mixture of isopropyl acetate (10 mL) and water (0.6mL) was heated to reflux with stirring. The compound was not completelydissolved so isopropyl acetate (10 mL) and water (0.6 mL) were added andheated to reflux. Stirring was stopped and the experiment was allowed tocool to room temperature. The crystalline product obtained were isolatedby filtration and dried in vacuo at 40° C. Yield=0.25 g, mp=183.7° C.(DSC onset value). XRPD analysis conforms with the alpha form.

Method IV:

0.5g Compound I in a mixture of ethyl acetate (10 mL) and water (0.4 mL)was heated to 70° C. with stirring. The experiment was allowed to coolto room temperature. The crystalline product obtained were isolated byfiltration and dried in vacuo at 40° C. XRPD analysis conforms with thealpha form.

Example 2 Preparation of Crystalline Beta Form of Compound I

28.0 g amorphous Compound I was dissolved in 250 ml tetrahydrofuran(THF) and evaporated onto 60 g silica gel. The compound was purified bycolumn chromatography on silica gel (Ø: 10 cm h: 5 cm with 2.7 lTHF/heptane 2/1). The eluent containing the desired compound wasevaporated a rotary evaporator at reduced pressure at 50° C. to a solid(26 g). The solid was suspended in 600 ml isopropyl acetate and thesuspension heated to reflux until almost all material was dissolved. Thesuspension was cooled on a water/ice bath. The cold suspension wasfiltered, and the filter cake was washed with isopropyl acetate anddried in vacuo overnight at 50° C.

Yield: 16.9 g (61%), mp=211.7° C. (DSC onset value), Weight loss byheating: 0.2%, Elemental analysis: 6.59% N, 64.63% C, 5.41% H,theoretical values: 6.82% N, 64.37% C, 5.40% H, XRPD analysis conformswith the beta form.

Example 3 Preparation of Crystalline Gamma Form of Compound I

Method I:

15 g amorphous Compound I was dissolved in 75 ml acetone. 1.5 gpotassium carbonate was added and the suspension stirred for 90 minutes.The suspension was filtered. The filtrate was reduced to approximately30 ml on a rotary evaporator at reduced pressure at 60° C. 150 mlMethanol was added to the reduced filtrate, and some sticky materialseparated. The suspension was heated to reflux. During the heating allmaterial dissolves. The solution was allowed to cool to room temperatureby natural cooling, during this period solid material separated. Thesuspension was left with stirring at room temperature overnight.

The suspension was filtered and the filter cake washed with methanol.The filter cake was dried in vacuo at 50° C. overnight. Intermediateyield is 10.2 gram (68%).

The dry filter cake was suspended in 100 ml acetonitrile (ACN) andheated to reflux. At reflux a turbid solution was obtained. Additionalacetonitrile was added until a clear solution was obtained; in total thefilter cake was dissolved in 200 ml acetonitrile including the 100 mlused for suspension.

The solution was cooled to room temperature overnight. The following daythe crystalline product was isolated by filtration. The filter cake waswashed by a small amount of acetonitrile and dried in vacuo at 55° C.overnight.

Yield: 6.17 g, 41%, mp=218.0° C. (DSC onset value), Weight loss byheating: <0.1%, Elemental analysis: 6.80% N, 64.38% C, 5.43% H,theoretical values: 6.82% N, 64.37% C, 5.40% H, Purity (HPLC, area %):98.6, XRPD analysis conforms with the gamma form.

Method II:

0.5 g Compound I in a mixture of acetonitrile (8.8 mL) and water (1.2mL) was heated to 70 C with stirring. The solution was allowed to coolslowly to room temperature. The next day the crystalline product wasisolated by filtration and dried in vacuo at 40° C., mp=214.2° C. (DSConset value) XRPD analysis conforms with the gamma form.

Method III:

0.5 g Compound I in ethyl acetate (5 mL) was heated to 70° C. withstirring. The solution was allowed to cool slowly to room temperature.After 12 days the crystalline product was isolated by filtration anddried in vacuo at 40° C. XRPD analysis conforms with the gamma form.

Example 4 Preparation of Crystalline Delta Form of Compound I

Method I:

0.5 g alpha form Compound I in cyclopropyl methanol (10 mL) was heatedto 70° C. The solution was allowed to cool slowly to room temperature.After 2 days the crystalline compound was isolated by filtration anddried in vacuo at 40° C. Yield=0.24 g, mp=212.1° C. (DSC onset value),XRPD analysis conforms with the delta form.

Method II:

0.2 g alpha form Compound I in ethanol (10 mL) was heated to 70° C. withstirring. The stirring was stopped and the solution was allowed to coolslowly to room temperature. The next day the crystalline product wasisolated by filtration and dried in vacuo at 40° C. Yield=0.15 g,mp=221.6° C. (DSC onset value), XRPD analysis conforms with the deltaform

Method III:

0.5 g Compound I in 1-propanol (15 mL) was heated to 70° C. withstirring. The stirring was stopped and the solution was allowed to coolslowly to room temperature. The next day the crystalline compound wasisolated by filtration and dried in vacuo at 40° C. Yield=0.23 g, XRPDanalysis conforms with the delta form.

Example 5 Preparation of Crystalline Epsilon Form of Compound I

0.5 g alpha form Compound I in butylnitrile (10 mL) was heated to 70° C.with stirring. The solution was allowed to cool slowly to roomtemperature. The next day the crystalline product was isolated byfiltration and dried in vacuo at 40° C. Yield=0.3 g, mp=181.8° C. (DSConset value), XRPD analysis conforms with the epsilon form.

Example 6 Transformation Between Different Solid Forms of Compound I

6.1 Conversions to Crystalline Compound I

In the following examples are used excess of solid Compound I, i.e.compared to the solvent the amounts of solid Compound I is such that notall the solid material comes into solution. The amounts used variedbetween 25-50 mg solid Compound I and 2-5 ml solvent. In the presentcontext by “solid Compound I” is meant amorphous Compound I or any ofthe crystalline forms of Compound I as indicated below.

(i) Excess of amorphous Compound I was added to methanol and theresulting suspension was stored on a rotarmix for 4 days at roomtemperature. After 4 days the solid was the alpha form as determined bypowder X-ray diffraction.

(ii) Excess of the crystalline alpha form of Compound I was added tomethanol and the resulting suspension was stored on a rotarmix for 4days at room temperature. After 4 days the solid was still the alphaform as determined by powder X-ray diffraction.

(iii) Excess of the crystalline beta form of Compound I was added tomethanol and the resulting suspension was stored on a rotarmix for 4days at room temperature. After 4 days the solid was the alpha form asdetermined by powder X-ray diffraction.

(iv) Excess of the crystalline gamma form of Compound I was added tomethanol and the resulting suspension was stored on a rotarmix for 4days at room temperature. After 4 days the solid was still the gammaform as determined by powder X-ray diffraction.

(v) Excess of a 1:1 mixture of the alpha and the gamma form of CompoundI was added to methanol and the resulting suspension was stored on arotarmix stored for 4 days at room temperature. After 4 days the majorpart of the solid was the gamma form. After filtration the supernatantwas left for evaporation of the solvent. The resulting solid was thealpha form as determined by powder X-ray diffraction.

(vi) Excess of amorphous Compound I was added to acetonitrile (ACN) andthe resulting suspension was stored on a rotarmix for 4 days at roomtemperature. After 4 days the solid was the gamma form as determined bypowder X-ray diffraction.

(vii) Excess of the crystalline alpha form of Compound I was added toACN and the resulting suspension was stored on a rotarmix for 4 days atroom temperature. After 4 days the solid was the gamma form asdetermined by powder X-ray diffraction.

(viii) Excess of the crystalline beta form of Compound I was added toACN and the resulting suspension was stored on a rotarmix for 4 days atroom temperature. After 4 days the solid was the gamma form asdetermined by powder X-ray diffraction.

(ix) Excess of the crystalline gamma form of Compound I was added to ACNand the resulting suspension was stored on a rotarmix for 4 days at roomtemperature. After 4 days the solid was still the gamma form asdetermined by powder X-ray diffraction.

Conclusion:

Amorphous Compound I and the crystalline beta form can be converted intocrystalline alpha form in a methanol suspension.

Amorphous Compound I, the crystalline alpha form and the crystallinebeta form can be converted into the crystalline gamma form by suspensionof excess of the solid material in acetonitrile.

6.2 Conversions from Crystalline Alpha Form to Amorphous Compound I

15 g crystalline alpha form of Compound I was heated to reflux in amixture of Toluene (110 mL) and methanol (1 mL); a clear solution wasobtained. Under reduced pressure the solvent volume was decreased by 10mL and the solution was cooled overnight in a freezer. The resultingsolid was isolated by filtration, dried in vacuo over two days at 40° C.to give 13.2 g of a solid. The melting temperature of the solid wasapprox. 150° C. which characterises the amorphous form of Compound I ascompared to the crystalline forms, cf. Table 1 below.

Example 7 Analytical Methods

(7.1) XRPD patterns were measured on a Diffractometer under one of thefollowing conditions:

-   -   (i) STOE diffractometer    -   Radiation: Cu(Kα1), germanium monochromator, λ=1.540598 Å    -   Position Sensitive Detector (PSD) covering 7°    -   Scan type: Step scan, steps: 0.1°, 125-150 sec. pr. step    -   Range: 5-45°2θ    -   Sample measuring method: Transmission    -   (ii) PANalytical X′Pert PRO X-Ray Diffractometer using CuK_(α1)        radiation.    -   X′celerator detector, measuring the range 5-40°2θ.    -   Sample measuring method: Reflection

(7.2) The solid state NMR was performed under the following conditions:

-   -   The Carbon-13 CP/MAS (cross-polarization/magic-angle spinning)        NMR spectra were acquired at room temperature at 11.75 Tesla on        a Bruker Avance DRX-500 spectrometer equipped with a 4 mm CP/MAS        probe. The sample spinning speed was 5000 Hz, and 10240 scans        were acquired using a recycle delay of 5 sec. For the cross        polarization, spin-lock radio frequency fields of 50 kHz and a        contact time of 5 msec were employed.

(7.3) Near-infrared (NIR) data were collected with Bomem MB 160 FT/NIRspectrometer with Powder SamplIR. The NIR reflectance spectra wererecorded between 14.000-4.000 cm-1 with resolution 2 cm-1 (16 scans,high gain). Baseline shift and slope in NIR spectra, which is often seenin powder, were removed with Multiplicative Scatter Correction (MSC).

(7.4) Melting points were determined on a DSC (Differential ScanningCalorimeter) as the onset temperature of the melting endotherm. About 2mg of sample was heated in an aluminium crucible with loose lid, at 5°C./min under N₂ flow.

(7.5) The crystal structure of the alpha form was determined under thefollowing conditions: The diffraction data were collected on a NoniusKappaCCD diffractometer. The data collection was performed at 122 Kusing monochromatized MoK_(α), radiation (λ=0.71073 Å).

Example 8 Analytical Results

8.1 X-ray powder data: The X-ray powder diffractogram (XRPD) of; thealpha form is shown in FIG. 1; the beta form is shown in FIG. 2; thegamma form is shown in FIG. 3; the delta form is shown in FIG. 13; theepsilon form is shown in FIG. 15. The different crystalline forms arecharacterized by different reflections (peaks) in the X-Ray powderdiffractogram as measured using CuKα radiation at 2-theta anglesdetermined:

Alpha (5.2, 10.1, 10.4, 13.2, 15.1, 25.1; 5.2, 7.3, 8.1, 10.1, 10.4,11.2, 13.2, 15.1, 15.5, 17.3, 21.7, 23.8, 25.1);

Beta (6.6, 8.9, 10.7, 11.7, 24.4, 30.6; 6.6, 8.9, 10.7, 11.4, 11.7,13.7, 17.0, 18.5, 18.8, 19.2, 20.3, 24.4, 30.6);

Gamma (9.6, 11.5, 12.5, 16.7, 19.3, 28.1; 7.5, 8.3, 9.6, 11.5, 11.8,12.5, 15.9, 16.3, 16.7, 17.2, 18.0, 19.3, 21.0, 28.1);

Delta (9.7, 12.1, 16.1, 18.3, 22.1, 22.2, 25.7, 25.8; 7.3, 8.3, 9.7,11.1, 11.7, 12.1, 15.6, 16.1, 17.3, 18.3, 20.9, 22.1, 22.2, 25.7, 25.8);

Epsilon (8.9, 9.2, 10.2, 14.6; 8.9, 9.2, 10.2, 12.6, 14.2, 14.6, 17.0,18.6, 20.4, 21.1, 23.9, 25.2).

8.2. DSC thermograms: The DSC thermograms are shown in FIGS. 4-6, 14, 16(alpha form in FIG. 4; beta form in FIG. 5; and gamma form in FIG. 6,delta form in FIG. 14, epsilon form in FIG. 16).

8.3. Solid state NMR data: The solid state NMR spectra are shown in FIG.7 for the alpha form, FIG. 8 for the beta form and FIG. 9 for the gammaform.

8.4 NIR data: The NIR-spectra are shown in FIG. 10 for the alpha form,FIG. 11 for the beta form and FIG. 12 for the gamma form.

8.5 Crystal structure for Compound I alpha form: The crystal structureof the alpha form was determined by single crystal X-ray diffraction at122 K. The crystal used for the structure determination was obtained byslow precipitation from MeOH and had dimensions 0.5×0.3×0.2 mm.

The resulting crystal structure shows that the alpha form of Compound Icrystallizes in the orthorhombic space group P2₁2₁2₁ with the celldimensions at 122 K of: a=10.227(2) Å, b=23.942(2) Å and c=24.240(2) Å,α=90°, β=90°, γ=90°, V=5935.3(12) Å³, Z=8, density=1.378 g/cm³ (thenumbers in parenthesis are standard deviations on the last digit). Theun-weighted agreement factor was R[I>2G(I)]=0.0699.

The asymmetric unit of the crystal contains two Compound I units, and0-1 solvent molecule. The solvent molecule may be either MeOH or water.In the structure determination the atoms corresponding to solvent werefound with an occupancy of C2″:0.70, O1″:0.50 and O3″:0.36. As theasymmetric unit contains 2 molecules of Compound I and one solvent site,full occupancy of the site would lead to a hemi-solvate. The atomnumbering and the conformation of the two molecules in the asymmetricunit are shown in FIGS. 17-18, and the packing of the molecules in thecrystal is shown in FIG. 19. The atom coordinates are given in Tables2-4 below.

TABLE 2 Atom coordinates and equivalent isotropic displacementparameters for non-hydrogen atoms in molecule 1 Label X y z U_(eq) C11−0.1062(9) 0.2071(4) 0.3154(5) 0.119(4) C12 −0.0922(7) 0.2369(3)0.2679(4) 0.097(3) C13 0.0402(5) 0.3338(2) 0.3022(2) 0.0517(13) C140.1485(4) 0.37791(19) 0.29800(19) 0.0414(10) C15 0.1730(5) 0.4125(2)0.34227(19) 0.0482(12) C16 0.2157(4) 0.38580(16) 0.24912(17) 0.0331(8)C17 0.2642(4) 0.4561(2) 0.34044(17) 0.0396(9) C18 0.3097(3) 0.42813(15)0.24665(15) 0.0278(7) C19 0.3347(4) 0.46402(17) 0.29167(15) 0.0320(8)C20 0.3600(3) 0.37367(14) 0.12235(15) 0.0271(7) C21 0.4226(3)0.42266(13) 0.15070(14) 0.0233(6) C22 0.3963(3) 0.44422(14) 0.20324(14)0.0238(6) C23 0.4700(3) 0.48995(14) 0.22250(14) 0.0241(6) C24 0.5184(3)0.41458(14) 0.06419(15) 0.0264(7) C25 0.5168(3) 0.44565(13) 0.11709(13)0.0215(6) C26 0.5911(3) 0.49186(13) 0.13513(13) 0.0213(6) C27 0.5642(3)0.51352(14) 0.18804(13) 0.0230(6) C28 0.6972(3) 0.52525(14) 0.11306(14)0.0228(6) C29 0.7277(3) 0.56606(14) 0.15290(13) 0.0234(6) C30 0.7685(4)0.52346(14) 0.06360(14) 0.0253(7) C31 0.8269(4) 0.60505(15) 0.14453(16)0.0298(7) C32 0.8676(3) 0.56175(15) 0.05494(15) 0.0269(7) C33 0.8947(4)0.60199(15) 0.09522(16) 0.0298(7) C34 0.9449(4) 0.55929(17) 0.00224(16)0.0334(8) C35 0.7493(5) 0.6209(3) −0.0511(2) 0.0599(15) C36 0.6968(6)0.5714(4) −0.0827(3) 0.083(2) C37 0.5095(5) 0.52590(19) 0.37193(15)0.0392(9) C38 0.4993(4) 0.54457(16) 0.31227(14) 0.0293(7) C39 0.4323(4)0.60294(16) 0.30392(13) 0.0297(7) C40 0.4783(4) 0.64389(17) 0.34996(14)0.0345(9) C41 0.6244(4) 0.59217(15) 0.24601(14) 0.0279(7) C42 0.4889(4)0.61943(15) 0.24753(14) 0.0282(7) C43 0.6494(6) 0.7018(2) 0.3803(2)0.0550(13) N10 0.6453(3) 0.55884(12) 0.19786(12) 0.0273(6) N8 0.4287(3)0.37320(12) 0.07002(13) 0.0299(6) N9 0.4351(3) 0.50175(13) 0.27731(12)0.0276(6) O3 0.5841(3) 0.42305(12) 0.02296(11) 0.0336(6) O4 0.6272(3)0.55359(11) 0.29230(10) 0.0294(5) O5 0.2968(3) 0.60128(12) 0.30872(10)0.0334(6) O6 0.4183(4) 0.65298(14) 0.39104(11) 0.0475(8) O7 0.5939(3)0.66596(12) 0.33752(12) 0.0417(7) S1 0.05826(13) 0.27639(6) 0.25442(6)0.0573(3) S2 0.92480(12) 0.61925(5) −0.04247(5) 0.0462(3)

TABLE 3 Atom coordinates and equivalent isotropic displacementparameters for non-hydrogen atoms in molecule2 label x y z U_(eq) C11′0.3351(9) 0.2274(4) 0.3741(4) 0.107(3) C12′ 0.4501(6) 0.2572(2)0.3960(2) 0.0535(12) C13′ 0.5141(4) 0.32653(17) 0.30754(16) 0.0320(8)C14′ 0.5962(3) 0.33381(15) 0.25640(15) 0.0284(7) C15′ 0.5818(4)0.29548(15) 0.21266(15) 0.0295(7) C16′ 0.6877(3) 0.37626(15) 0.25214(15)0.0264(7) C17′ 0.6562(4) 0.29896(16) 0.16476(15) 0.0309(8) C18′0.7644(3) 0.38027(14) 0.20460(14) 0.0245(7) C19′ 0.7470(3) 0.34216(14)0.16046(14) 0.0246(7) C20′ 0.9106(4) 0.48618(16) 0.27155(15) 0.0295(7)C21′ 0.9305(3) 0.46300(14) 0.21451(13) 0.0242(6) C22′ 0.8668(3)0.41839(14) 0.18834(14) 0.0241(7) C23′ 0.9068(3) 0.40231(14) 0.13561(13)0.0228(6) C24′ 1.0826(4) 0.53365(16) 0.22661(16) 0.0315(8) C25′1.0299(3) 0.49163(14) 0.18830(14) 0.0250(7) C26′ 1.0715(4) 0.47630(14)0.13450(14) 0.0254(7) C27′ 1.0087(3) 0.43081(14) 0.10898(14) 0.0244(6)C28′ 1.1674(4) 0.49705(15) 0.09601(15) 0.0268(7) C29′ 1.1603(4)0.46218(15) 0.04887(15) 0.0285(7) C30′ 1.2564(4) 0.54209(16) 0.09568(16)0.0306(7) C31′ 1.2411(4) 0.47048(16) 0.00324(16) 0.0345(8) C32′1.3357(4) 0.55112(17) 0.05095(17) 0.0339(8) C33′ 1.3282(4) 0.51493(18)0.00434(18) 0.0374(9) C34′ 1.4330(4) 0.59844(19) 0.0511(2) 0.0440(10)C35′ 1.2623(6) 0.6661(3) −0.0105(4) 0.077(2) C36′ 1.2183(8) 0.7019(6)0.0358(4) 0.136(5) C37′ 0.7433(4) 0.29800(18) 0.04312(16) 0.0338(8) C38′0.8600(3) 0.33047(15) 0.06463(14) 0.0262(7) C39′ 0.9950(3) 0.29655(14)0.06725(13) 0.0230(6) C40′ 0.9652(3) 0.23557(15) 0.05516(16) 0.0300(7)C41′ 1.0178(4) 0.38189(15) 0.01728(14) 0.0296(7) C42′ 1.0759(4)0.32366(14) 0.02225(14) 0.0267(7) C43′ 0.9026(12) 0.1491(3) 0.0916(4)0.121(4) N10′ 1.0640(3) 0.42245(12) 0.05746(12) 0.0279(6) N8′ 1.0092(3)0.53082(14) 0.27242(14) 0.0346(7) N9′ 0.8335(3) 0.35665(13) 0.11793(12)0.0251(6) O3′ 1.1773(3) 0.56475(12) 0.21928(12) 0.0378(6) O4′ 0.8822(3)0.37370(11) 0.02552(10) 0.0306(6) O5′ 1.0630(2) 0.30320(10) 0.11731(10)0.0262(5) O6′ 0.9505(3) 0.21745(12) 0.00864(13) 0.0396(7) O7′ 0.9482(4)0.20628(14) 0.10012(14) 0.0570(10) S1′ 0.57873(14) 0.26806(5) 0.34631(5)0.0507(3) S2′ 1.42524(15) 0.64612(5) −0.00597(6) 0.0561(3)

TABLE 4 Atom coordinates and equivalent isotropic displacementparameters and occupancy for atoms in the solvent entity Occu- label x yz U_(eq) pancy O1″ 0.7366(10) 0.4173(4) −0.0687(3) 0.080(4) 0.499(16)C2″ 0.6529(11) 0.4259(10) −0.1061(5) 0.143(10) 0.70(3) O3″ 0.5557(18)0.4565(8) −0.0933(5) 0.097(8) 0.36(2)

Example 9 Melting Points

The melting points (cf. Example 7.4 above) obtained for the amorphousform and the crystalline alpha, beta, gamma delta and epsilon solid formof Compound I are shown in Table 1 below.

TABLE 1 Form Approx. melting temperature: Amorphous approx. 150° C. α  181-189° C. β approx. 211° C. γ   212-218° C. δ 211-223 ε approx. 182

1. A crystalline form of Compound I, which has the formula:


2. A crystalline form according to claim 1, characterized by one or moreof: (i) the X-Ray powder diffractogram shown in FIG. 1 as measured usingCuKα radiation; (ii) reflections in the X-Ray powder diffractogram asmeasured using CuKα radiation at 2-theta angles: 5.2, 10.1, 10.4, 13.2,15.1, 25.1; (iii) the solid state Carbon-13 NMR spectrum shown in FIG.7; (iv) the NIR reflectance spectrum shown in FIG.
 10. 3. A crystallineform according to claim 2, characterized by reflections in the X-Raypowder diffractogram as measured using CuKα radiation at 2-theta angles:5.2, 10.1, 10.4, 13.2, 15.1, 25.1.
 4. A crystalline form according toclaim 3, characterized by reflections in the X-Ray powder diffractogramas measured using CuKα radiation at 2-theta angles: 5.2, 7.3, 8.1, 10.1,10.4, 11.2, 13.2, 15.1, 15.5, 17.3, 21.7, 23.8, 25.1.
 5. A crystallineform according to claim 1, characterized by having a crystal structurewith the following characteristics at 122 K: Space group: P2₁2₁2₁, Unitcell dimensions: a=10.227(2) Å, b=23.942(2) Å and c=24.240(2) Å, α=90°,β=90°, γ=90°, 2 molecules in the asymmetric unit.
 6. A crystalline formaccording to claim 1, characterized by one or more of: (i) the X-Raypowder diffractogram shown in FIG. 2 as measured using CuKα radiation;(ii) reflections in the X-Ray powder diffractogram as measured usingCuKα radiation at 2-theta angles: 6.6, 8.9, 10.7, 11.7, 24.4, 30.6;(iii) the solid state Carbon-13 NMR spectrum shown in FIG. 8; (iv) theNIR reflectance spectrum shown in FIG.
 11. 7. A crystalline formaccording to claim 6, characterized by reflections in the X-Ray powderdiffractogram as measured using CuKα radiation at 2-theta angles: 6.6,8.9, 10.7, 11.7, 24.4, 30.6.
 8. A crystalline form according to claim 1,characterized by reflections in the X-Ray powder diffractogram asmeasured using CuKα radiation at 2-theta angles: 6.6, 8.9, 10.7, 11.4,11.7, 13.7, 17.0, 18.5, 18.8, 19.2, 20.3, 24.4, 30.6.
 9. A crystallineform according to claim 1, characterized by one or more of: (i) theX-Ray powder diffractogram shown in FIG. 3 as measured using CuKαradiation; (ii) reflections in the X-Ray powder diffractogram asmeasured using CuKα radiation at 2-theta angles: 9.6, 11.5, 12.5, 16.7,19.3, 28.1; (iii) the solid state Carbon-13 NMR spectrum shown in FIG.9; (iv) the NIR reflectance spectrum shown in FIG.
 12. 10. A crystallineform according to claim 1, characterized by reflections in the X-Raypowder diffractogram as measured using CuKα radiation at 2-theta angles:9.6, 11.5, 12.5, 16.7, 19.3, 28.1.
 11. A crystalline form according toclaim 1, characterized by reflections in the X-Ray powder diffractogramas measured using CuKα radiation at 2-theta angles: 7.5, 8.3, 9.6, 11.5,11.8, 12.5, 15.9, 16.3, 16.7, 17.2, 18.0, 19.3, 21.0, 28.1.
 12. Acrystalline form according to claim 1, characterized by the X-Ray powderdiffractogram substantially as shown in FIG. 13 as measured using CuKαradiation.
 13. A crystalline form according to claim 1, characterized byreflections in the X-Ray powder diffractogram as measured using CuKαradiation at 2-theta angles: 9.7, 12.1, 16.1, 18.3, 22.1, 22.2, 25.7,25.8.
 14. A crystalline form according to claim 1, characterized byreflections in the X-Ray powder diffractogram as measured using CuKαradiation at 2-theta angles: 7.3, 8.3, 9.7, 11.1, 11.7, 12.1, 15.6,16.1, 17.3, 18.3, 20.9, 22.1, 22.2, 25.7, 25.8.
 15. A crystalline formaccording to claim 1, characterized by the X-Ray powder diffractogramsubstantially as shown in FIG. 15 as measured using CuKα radiation. 16.A crystalline form according to claim 1, characterized by reflections inthe X-Ray powder diffractogram as measured using CuKα radiation at2-theta angles: 8.9, 9.2, 10.2, 14.6.
 17. A crystalline form accordingto claim 1, characterized by reflections in the X-Ray powderdiffractogram as measured using CuKα radiation at 2-theta angles: 8.9,9.2, 10.2, 12.6, 14.2, 14.6, 17.0, 18.6, 20.4, 21.1, 23.9, 25.2.
 18. Acrystalline form according to claim 1 which is substantially pure.
 19. Apharmaceutical composition comprising crystalline Compound I, which hasthe formula:

and a pharmaceutically acceptable excipient.
 20. A pharmaceuticalcomposition according to claim 19 wherein the composition is a solidformulation.
 21. A pharmaceutical composition according to claim 19wherein the composition is a solid dispersion or a solid solutionformulation.
 22. A method of treating a CNS disease comprisingadministering a pharmaceutically effective amount of crystallineCompound I, which has the formula:


23. A method according to claim 22, wherein said CNS disease is aneurodegenerative disease.
 24. A method according to claim 23, whereinsaid disease is selected from the group consisting of Parkinson'sdisease, Alzheimer's disease, Huntington's disease, peripheralneuropathy, or AIDS dementia.